U.S. patent application number 13/797075 was filed with the patent office on 2014-09-18 for balanced port sense profile for improved capacity performance.
This patent application is currently assigned to Emerson Process Management Regulator Technologies, Inc.. The applicant listed for this patent is Emerson Process Management Regulator Technologies, Inc.. Invention is credited to GuoLei Fan, Jason S. Mevius, Biao Zhou.
Application Number | 20140261724 13/797075 |
Document ID | / |
Family ID | 50405180 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140261724 |
Kind Code |
A1 |
Fan; GuoLei ; et
al. |
September 18, 2014 |
Balanced Port Sense Profile for Improved Capacity Performance
Abstract
A fluid regulating device includes a regulator valve having an
inlet, an outlet, and a valve port disposed between the inlet and
the outlet. An actuator is coupled to the regulator valve and
includes a valve disc that displaces along a longitudinal axis to
open and close the fluid regulating device. The valve disc includes
a sealing surface disposed adjacent to an outer radial end of the
valve disc, and the sealing surface is adapted to sealingly engage
the valve port in the closed position. The valve disc also includes
an intermediate surface disposed inward of the sealing surface, and
a groove is formed in the intermediate surface. The groove extends
along a groove axis extending along the intermediate surface normal
to the longitudinal axis, and the groove axis is at least partially
curved when viewed along the longitudinal axis.
Inventors: |
Fan; GuoLei; (Chengdu,
CN) ; Zhou; Biao; (Chengdu, CN) ; Mevius;
Jason S.; (McKinney, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Technologies, Inc.; Emerson Process Management Regulator |
|
|
US |
|
|
Assignee: |
Emerson Process Management
Regulator Technologies, Inc.
McKinney
TX
|
Family ID: |
50405180 |
Appl. No.: |
13/797075 |
Filed: |
March 12, 2013 |
Current U.S.
Class: |
137/15.01 ;
137/484.6 |
Current CPC
Class: |
F16K 31/1262 20130101;
F16K 31/126 20130101; F16K 1/36 20130101; Y10T 137/7756 20150401;
Y10T 137/0402 20150401 |
Class at
Publication: |
137/15.01 ;
137/484.6 |
International
Class: |
F16K 31/126 20060101
F16K031/126 |
Claims
1. A fluid regulating device, comprising: a regulator valve having
an inlet, an outlet, and a valve port disposed between the inlet
and the outlet; an actuator coupled to the regulator valve and
comprising a valve disc, the valve disc disposed within the
regulator valve and adapted for displacement along a longitudinal
axis between a closed position sealingly engaging the valve port
and an open position disposed away from the valve port; the valve
disc including: a sealing surface disposed adjacent to an outer
radial end of the valve disc, the sealing surface adapted to
sealingly engage the valve port in the closed position; an
intermediate surface disposed radially inward of the sealing
surface; and a groove formed in the intermediate surface, the
groove extending along a groove axis extending along the
intermediate surface normal to the longitudinal axis, the groove
axis being at least partially curved when viewed along the
longitudinal axis.
2. The fluid regulating device of claim 1, wherein the groove axis
has a circular shape when viewed along the longitudinal axis.
3. The fluid regulating device of claim 1, wherein the groove axis
has a partially-circular shape when viewed along the longitudinal
axis.
4. The fluid regulating device of claim 1, wherein groove has a
constant cross-sectional shape when viewed along the groove
axis.
5. The fluid regulating device of claim 1, wherein the groove has a
planar top wall that is normal to the longitudinal axis.
6. The fluid regulating device of claim 5, wherein the groove has a
trapezoidal cross-sectional shape when viewed normal to the groove
axis, the trapezoidal cross-sectional shape including a first side
wall and a second side wall that each inwardly taper as each of the
first and second side walls extends away from the intermediate
surface and towards the top wall.
7. The fluid regulating device of claim 6, wherein the trapezoidal
cross-sectional shape is symmetrically formed about an axis normal
to the groove axis.
8. The fluid regulating device of claim 5, wherein the groove has
an at least partially curved cross-sectional shape when viewed
normal to the groove axis.
9. The fluid regulating device of claim 1, further comprising a
balancing spring acting on a portion of the valve disc to bias the
valve disc into the open position.
10. The fluid regulating device of claim 9, wherein the balancing
spring is chosen from a plurality of balancing springs to achieve
desired flow conditions through the fluid regulating device.
11. A fluid regulating device, comprising: a regulator valve having
an inlet, an outlet, and a valve port disposed between the inlet
and the outlet; an actuator coupled to the regulator valve and
comprising a valve disc, the valve disc disposed within the
regulator valve and adapted for displacement along a longitudinal
axis between a closed position sealingly engaging the valve port
and an open position disposed away from the valve port; the valve
disc including: a sealing surface disposed adjacent to an outer
radial end of the valve disc, the sealing surface adapted to
sealingly engage the valve port in the closed position; and an
intermediate surface disposed radially inward of the sealing
surface, wherein the intermediate surface includes a protrusion
that extends along the longitudinal axis towards the valve
port.
12. The fluid regulating device of claim 11, wherein a
cross-section of the intermediate surface includes a first edge and
a second edge, and the first edge and the second edge converge as
the intermediate surface extends towards the valve port.
13. The fluid regulating device of claim 12, wherein the first edge
and the second edge are symmetrical about the longitudinal
axis.
14. The fluid regulating device of claim 12, wherein the
intermediate surface is at least partially conical in shape.
15. The fluid regulating device of claim 12, wherein the
intermediate surface has the cross-sectional shape of a
parabola.
16. The fluid regulating device of claim 12, wherein the first edge
and the second edge are linear.
17. The fluid regulating device of claim 12, wherein the first edge
and the second edge are at least partially curved.
18. The fluid regulating device of claim 14, wherein the
intermediate surface has the shape of a cone, and a base of the
cone may have a radial length that is between three times the
longitudinal height of the cone and equal to the longitudinal
height of the cone.
19. The fluid regulating device of claim 15, wherein a radial width
of the parabola is between three times the longitudinal height of
the parabola and equal to the longitudinal height of the
parabola.
20. The fluid regulating device of claim 11, further comprising a
balancing spring acting on a portion of the valve disc to bias the
valve disc into the open position.
21. The fluid regulating device of claim 20, wherein the balancing
spring is chosen from a plurality of balancing springs to achieve
desired flow conditions through the fluid regulating device.
22. A method of tuning a balanced trim assembly of a fluid
regulating device, the method comprising: selecting a balancing
spring from a plurality of balancing springs, wherein each of the
plurality of balancing springs has a unique spring force; and
positioning the balancing spring within a fluid regulating device
such that the balancing spring biases a valve disc of the balanced
trim assembly away from a valve port and into an open position,
wherein the valve disc includes one of (1) a groove formed in an
intermediate surface of the valve disc that is disposed inward of a
sealing surface adapted to sealing engage the valve port in a
closed position, the groove extending along a groove axis extending
along the intermediate surface normal to a longitudinal axis
extending through the valve disc, the groove axis being at least
partially curved when viewed along the longitudinal axis, and (2)
an intermediate surface disposed radially inward of a sealing
surface adapted to sealing engage the valve port in a closed
position, wherein the intermediate surface includes a protrusion
that extends along a longitudinal axis extending through the valve
disc.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to fluid flow regulating
devices such as gas regulators and, more particularly, to gas
regulators having a balanced trim assembly.
BACKGROUND
[0002] The pressure at which typical gas distribution systems
supply gas may vary according to the demands placed on the system,
the climate, the source of supply, and/or other factors. However,
most end-user facilities equipped with gas appliances such as
furnaces, ovens, etc., require the gas to be delivered in
accordance with a predetermined pressure, and at or below a maximum
capacity of a gas regulator. Therefore, gas regulators are
implemented into these distribution systems to ensure that the
delivered gas meets the requirements of the end-user facilities.
Conventional gas regulators generally include a closed-loop control
actuator for sensing and controlling the pressure of the delivered
gas.
[0003] In addition to a closed loop control, some conventional gas
regulators include a balanced trim to improve the reaction of the
gas regulator to variations in the downstream pressure. The
balanced trim is adapted to reduce the influence of the upstream
pressure on the performance of the gas regulator. In conventional
regulators having a balanced trim, fluid travels from the inlet to
the outlet through a valve port when a sealing surface of a valve
disc is longitudinally displaced from a seating surface of the
valve port. As fluid flows through the valve port, the fluid acts
of the planar face of the valve disc. A portion of the fluid
flowing through the valve port may travel through channels disposed
through the planar face of the valve disc and that longitudinally
extend through the valve disc, and the channels open to a balancing
cavity that is at least partially defined by the balancing
diaphragm. So configured, upstream pressure is placed in fluid
communication with the balancing diaphragm to apply a force to the
valve disc of the gas regulator in the opposite direction as the
force of the downstream pressure (i.e., a "boost"). Accordingly, as
the upstream pressure varies, a corresponding force is applied to
balance the force created by the upstream pressure as described
further below so that the gas regulator acts in response to the
downstream pressure only. Such a configuration provides for a high
"boost" at a low inlet pressure, thereby resulting in the
undesirable reduction of capacity through the regulator. The
configuration also provides for a low "boost" at a high inlet
pressure, thereby resulting in the undesirable increase of capacity
through the regulator.
SUMMARY
[0004] A fluid regulating device includes a regulator valve having
an inlet, an outlet, and a valve port disposed between the inlet
and the outlet. An actuator is coupled to the regulator valve and
includes a valve disc, the valve disc being disposed within the
regulator valve and adapted for displacement along a longitudinal
axis between a closed position sealingly engaging the valve port
and an open position disposed away from the valve port. The valve
disc includes a sealing surface disposed adjacent to an outer
radial end of the valve disc, the sealing surface being adapted to
sealingly engage the valve port in the closed position. The valve
disc also includes an intermediate surface disposed inward of the
sealing surface. The valve disc further includes a groove formed in
the intermediate surface. The groove extends along a groove axis
extending along the intermediate surface normal to the longitudinal
axis, and the groove axis is at least partially curved when viewed
along the longitudinal axis.
[0005] In a further embodiment, a fluid regulating device includes
a regulator valve having an inlet, an outlet, and a valve port
disposed between the inlet and the outlet. An actuator is coupled
to the regulator valve and includes a valve disc, the valve disc
being disposed within the regulator valve and adapted for
displacement along a longitudinal axis between a closed position
sealingly engaging the valve port and an open position disposed
away from the valve port. The valve disc includes a sealing surface
disposed adjacent to an outer radial end of the valve disc, and the
sealing surface is adapted to sealingly engage the valve port in
the closed position. The valve disc further includes an
intermediate surface disposed radially inward of the sealing
surface, wherein the intermediate surface extends along the
longitudinal axis towards the valve port.
[0006] A method of tuning a balanced trim assembly of a fluid
regulating device includes selecting a balancing spring from a
plurality of balancing springs, wherein each of the plurality of
balancing springs has a unique spring force. The method also
includes positioning the balancing spring within a fluid regulating
device such that the balancing spring biases a valve disc of the
balanced trim assembly away from a valve port and into an open
position. The valve disc includes one of (1) a groove formed in an
intermediate surface of the valve disc that is disposed inward of a
sealing surface adapted to sealing engage the valve port in a
closed position, the groove extending along a groove axis extending
along the intermediate surface normal to a longitudinal axis
extending through the valve disc, the groove axis being at least
partially curved when viewed along the longitudinal axis, and (2)
an intermediate surface disposed radially inward of a sealing
surface adapted to sealing engage the valve port in a closed
position, wherein the intermediate surface includes a protrusion
that extends along a longitudinal axis extending through the valve
disc.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a side cross-sectional view of an embodiment of a
fluid regulating device in an open position;
[0008] FIG. 2 is a partial side cross-sectional view of the valve
disc and valve port of the fluid regulating device of FIG. 1;
[0009] FIG. 3A is a side cross-sectional view of an embodiment of
the valve disc;
[0010] FIG. 3B is a bottom view of the embodiment of the valve disc
of FIG. 3A;
[0011] FIG. 4 is a partial side cross-sectional view of a groove of
the embodiment of the valve disc of FIG. 3A;
[0012] FIG. 5A is a partial side cross-sectional view of a further
embodiment of the valve disc; and
[0013] FIG. 5B is a partial side cross-sectional view of a still
further embodiment of the valve disc.
DETAILED DESCRIPTION
[0014] FIGS. 1 and 2 illustrate a fluid regulating device 10
including a regulator valve 12 having an inlet 14, an outlet 16,
and a valve port 18 disposed between the inlet 14 and the outlet
16. An actuator 20 is coupled to the regulator valve 12 and
includes a valve disc 22, the valve disc 22 disposed within the
regulator valve 12 and adapted for displacement along a
longitudinal axis 24 between a closed position sealingly engaging
the valve port 18 and an open position disposed away from the valve
port 18. As shown in FIG. 3A, the valve disc 22 includes a sealing
surface 26 disposed adjacent to an outer radial end 28 of the valve
disc 22, the sealing surface 26 adapted to sealingly engage the
valve port 18 in the closed position. The valve disc 22 also
includes an intermediate surface 30 disposed inward of the sealing
surface 26.
[0015] As illustrated in FIGS. 3A, 3B, and 4, the valve disc 22
further includes a groove 32 formed in the intermediate surface 30,
the groove 32 extending along a groove axis 34 extending along the
intermediate surface 30 normal to the longitudinal axis 24, the
groove axis 34 being at least partially curved when viewed along
the longitudinal axis 24. In such a configuration, "boost" can be
increased at a high inlet pressure, thereby advantageously
decreasing capacity through the regulator.
[0016] In alternative embodiments illustrated in FIGS. 5A and 5B,
the intermediate surface 30' disposed radially inward of the
sealing surface 26, and the intermediate surface 30' includes a
protrusion 150 that extends along the longitudinal axis 24 towards
the valve port 18. In this embodiment, a cross-section of the
intermediate surface 30' includes a first edge 164 and a second
edge 166, and the first edge 164 and the second edge 166 converge
as the intermediate surface 30' extends towards the valve port 18.
So configured, "boost" can be reduced at a low inlet pressure,
thereby advantageously increasing capacity through the
regulator.
[0017] Turning to the fluid regulating device 10 in more detail,
the fluid regulating device 10 includes the actuator 20 and the
regulator valve 12, as illustrated in FIGS. 1 and 2. The regulator
valve 12 includes the inlet 14 for receiving gas from a gas
distribution system, for example, and the outlet 16 for delivering
gas to a facility having one or more appliances, for example. The
actuator 20 is coupled to the regulator valve 12 and includes a
control assembly 36 having a control element, such as a valve disc
22. During a first or normal operational mode, the control assembly
36 senses the pressure at the outlet 16 of the regulator valve 12
(i.e., the outlet pressure) and controls a position of the valve
disc 22 such that the outlet pressure approximately equals a
predetermined setpoint or control pressure.
[0018] With reference to FIGS. 1 and 2, the regulator valve 12
defines a throat 38 and a valve mouth 40. The throat 38 is disposed
between the inlet 14 and the outlet 16, and has the valve port 18
disposed therein. Fluid must travel through the valve port 18 to
travel between the inlet 14 and the outlet 16 of the regulator
valve 12. The valve port 18 may be removable from the regulator
valve 12 such that it may be replaced with a different valve port
having a bore of a different diameter or configuration to tailor
operational and flow characteristics of the regulator valve 12 to a
specific application. In the disclosed embodiment, the valve mouth
40 defines an opening disposed along an axis that is generally
parallel to the horizontal longitudinal axis 24 (i.e., along the X
axis of the reference coordinate system provided in FIG. 1) and
that is generally perpendicular to a vertical longitudinal axis
(i.e., an axis disposed along or parallel to the Y axis of the
reference coordinate system provided in FIG. 1) of the inlet 14 and
outlet 16 of the regulator valve 12.
[0019] Referring to FIG. 1, the actuator 20 includes a housing 42
and the control assembly 36, as discussed above. The housing 42
includes an upper housing component 42a and a lower housing
component 42b secured together with a plurality of fasteners, for
example. The lower housing component 42b defines a control cavity
44 and an actuator mouth 46. The actuator mouth 46 is connected to
the valve mouth 40 of the regulator valve 12 to provide fluid
communication between the actuator 20 and the regulator valve 12.
The upper housing component 42a defines a relief cavity 48 and a
tower portion 50 for accommodating a portion of the control
assembly 36, as will be described.
[0020] The control assembly 36 includes a diaphragm subassembly 52,
a disc and balancing subassembly 54, and a release valve 56. The
diaphragm subassembly 52 includes a diaphragm 58, a piston 60, a
control spring 62, a relief spring 64, a combination spring seat
68, a relief spring seat 72, a control spring seat 76, and a piston
guide 80. More particularly, the diaphragm 58 includes a
disc-shaped diaphragm defining an opening through a central portion
thereof. The diaphragm 58 is constructed of a flexible,
substantially air-tight, material and its periphery is sealingly
secured between the upper and lower housing components 42a, 42b of
the housing 42. The diaphragm 58 therefore separates the relief
cavity 48 from the control cavity 44.
[0021] The combination spring seat 68 is disposed on top of the
diaphragm 58 and defines an opening disposed concentric with the
opening in the diaphragm 58. As depicted in FIG. 1, the combination
spring seat 68 supports the control spring 62 and the relief spring
64.
[0022] The piston 60 of the disclosed embodiment includes a
generally elongated rod-shaped member having a sealing cup portion
84, a yoke 88, a threaded portion 92, and a guide portion 96. The
sealing cup portion 84 is concaved and generally disc-shaped and
extends circumferentially about a mid-portion of the piston 60, and
is located just below the diaphragm 58. The yoke 88 includes a
cavity adapted to accommodate a coupler 100 which connects to a
portion of the disc and balancing subassembly 54 to enable
attachment between the diaphragm subassembly 52 and the disc and
balancing subassembly 54, as will be described.
[0023] The guide portion 96 and the threaded portion 92 of the
piston 60 are disposed through the openings in the diaphragm 58 and
the combination spring seat 68, respectively. The guide portion 96
of the piston 60 is slidably disposed in a cavity in the piston
guide 80, which maintains the axial alignment of the piston 60
relative to the remainder of the control assembly 36. The relief
spring 64, the relief spring seat 72, and a nut 104 are disposed on
the threaded portion 92 of the piston 60. The nut 104 retains the
relief spring 64 between the combination spring seat 68 and the
relief spring seat 72. The control spring 62 is disposed on top of
the combination spring seat 68, as mentioned, and within the tower
portion 50 of the upper housing component 42a. The control spring
seat 74 is threaded into the tower portion 50 and compresses the
control spring 62 against the combination spring seat 68. In the
disclosed embodiment, the control spring 62 and the relief spring
64 include compression coil springs. Accordingly, the control
spring 62 is grounded against the upper housing component 42a and
applies a downward force to the combination spring seat 68 and the
diaphragm 58. The relief spring 64 is grounded against the
combination spring seat 68 and applies an upward force to the
relief spring seat 72, which in turn is applied to the piston 60.
In the disclosed embodiment, the force generated by the control
spring 62 is adjustable by adjusting the position of the control
spring seat 74 in the tower portion 50, and therefore the control
pressure of the regulator 10 is also adjustable.
[0024] The control spring 62 acts against the pressure in the
control cavity 44, which is sensed by the diaphragm 58. As stated,
this pressure is the same pressure as that which exists at the
outlet 16 of the regulator valve 12. Accordingly, the force applied
by the control spring 62 sets the outlet pressure to a desired
setpoint or control pressure for the regulator 10. The diaphragm
subassembly 52 is operably coupled to the valve disc 22 and
balancing subassembly 54, as mentioned above, via the yoke 88 of
the piston 60 and the coupler 100, and by a control arm 108.
[0025] The disc and balancing subassembly 54 includes an actuator
stem 112 that is engaged by the control arm 108 to move the valve
disc 22 between the open and closed positions as the diaphragm 58
flexes due to variations in the downstream pressure. Specifically,
the actuator stem 112 is a generally linear rod having an end
surface engaged by the control arm 108. The control arm 108 is a
slightly curved rod and includes a fulcrum end 108a and a free end
108b. The fulcrum end 108a is pivotally coupled to the lower
housing component 130b and includes a finger 113 having a rounded
end and engaging the end surface of the actuator stem 112. The free
end 108b is received between a top portion and a pin of the coupler
100 that is attached to the yoke 88 of the piston 60. Thus, the
coupler 100 and the control arm 108 operably connect the disc and
balancing subassembly 54 to the diaphragm subassembly 52.
[0026] As illustrated in FIG. 2, the valve disc 22 of the disc and
balancing subassembly 54 is operatively connected to the actuator
stem 112, and includes the sealing surface 26 that engages the
outlet of the valve port 18 to cut off the fluid flow through the
regulator valve 12. The valve disc 22 may be directly or indirectly
connected to the actuator stem 112 by a balanced port stem 116
(that is secured to the valve disc 22) and a balancing spring seat
120, and the combined elements are supported for linear movement by
a stem guide 124, a retainer plate 128, a balancing diaphragm
retainer 132 and a balancing port housing 136. The stem guide 124
is configured to fit within the actuator mouth 46, and includes a
generally cylindrical inner portion that slidably retains the
actuator stem 112. The stem guide 124 further includes channels 140
therethrough forming a portion of the path placing the outlet 16 in
fluid communication with control cavity 44 as discussed further
below.
[0027] Referring to FIG. 2, the stem guide 124 engages the retainer
plate 128, which is disposed between the stem guide 124 and
balanced port housing 136, to hold the retainer plate 128 and
balanced port housing 136 in place within the valve mouth 126. The
retainer plate 128 is generally circular and includes a central
opening through which the balanced port stem 116 passes. The
balanced port housing 136 is generally cylindrical and hollow,
extends toward the valve port 18, and has an inner diameter sized
to slidably receive the valve disc 22. The diaphragm retainer 132
is disposed within the balanced port housing 136 and the opening of
the retainer plate 128, and is held in place between a surface of
the retainer plate 128 and an inner shoulder of the balanced port
housing 136. A disc-shaped balancing diaphragm 144 having a central
opening is provided within the balanced port housing 136. The
balancing diaphragm 144 is constructed of a flexible, substantially
air-tight, material and its periphery is secured between the
diaphragm retainer 132 and the balanced port housing 136. The inner
edge at the central opening of the balancing diaphragm 144 is
sealingly secured between the valve disc 22 and the balanced port
stem 116. So configured, a first cavity 156 is formed between a
second end 154 of the valve disc 22, the diaphragm retainer 132,
and a surface of the balancing diaphragm 144.
[0028] The valve disc 22, the balanced port stem 116 secured to the
valve disc 22, and the actuator stem 112 may be biased toward the
open position of the regulator valve 12 by a balancing spring 148
disposed between the balancing spring seat 120 and a seating
surface of the diaphragm retainer 132. More specifically, the
seating surface of the diaphragm retainer 132 may be adapted to
seat a first end of the balancing spring 148 and a second end of
the balancing spring 148 may be adapted to engage a portion of the
balancing spring seat 120, as illustrated in FIG. 2. The balancing
spring 148 may be any suitable resilient member, such as a coil
spring that is coaxially aligned with the longitudinal axis 24.
Because the seating surface of the diaphragm retainer 132 is
stationary, the second end of the balancing spring 148 biases the
balancing spring seat 120 into engagement with the actuator stem
112. The balancing spring 148 may be pre-stressed to provide a
suitable biasing force regardless of the position of the actuator
stem 112. Moreover, the balancing spring 148 may be chosen from a
plurality of balancing springs that each have a unique spring
characteristics (e.g., spring force) to tune the disc and balancing
subassembly 54 to achieve desired flow conditions.
[0029] As illustrated in FIG. 3A, the valve disc 22 of the valve
disc includes the sealing surface 26 that disposed at a first end
152 of the valve disc 22, and the first end 152 is longitudinally
opposite the second end 154 of the valve disc 22. The sealing
surface 26 is disposed adjacent to the outer radial end 28 of the
valve disc 22, and the sealing surface 26 is adapted to sealingly
engage the valve port 18 in the closed position. The sealing
surface 26 may be a portion of a sealing insert secured within a
cavity formed in the valve disc 22 or may be a surface on the valve
disc 22 itself. The sealing surface 26 may include any suitable
material or combination of materials, such as a resilient,
compressible material. The intermediate surface 30 is disposed
radially inward of the sealing surface 26 (i.e., in a radial
direction towards the longitudinal axis 24) towards the first end
152 of the valve disc 22. The intermediate surface 30 may be a
portion of an insert secured to the valve disc 22 or may be a
surface on the valve disc 22 itself. The valve disc 22 may further
include one or more disc passages 155 that may longitudinally
extend through the valve disc 22 from the first end 152 to the
second end 154 such that the first cavity 156 is in fluid
communication with the area adjacent to outlet 125 of the valve
port 18. The one or more disc passages 155 may be formed as a
combination of one or more cylindrical passageways and one or more
planar passageways that extend through the valve disc 22. In
addition, one or more of the disc passages 155 may at least
partially include elongated longitudinal passageways having any
suitable cross-sectional shape (such as a round, ovular, or
polygonal, for example).
[0030] With the valve disc 22 in the open position, fluid flows
through the one or more disc passages 155 from the outlet 125 of
the valve port 18 into the first cavity 156 and into contact with
the balancing diaphragm 144. As such, the one or more disc passages
155 are configured to place the surface of the balancing diaphragm
144 opposite the valve port 18 in fluid communication with the
upstream pressure bearing on the valve disc 22. Accordingly, the
balancing diaphragm 144 provides a force on the valve disc 22 in
the direction of the valve port 18 to compensate for the force
applied to the valve disc 22 due to the upstream pressure of the
fluid passing through the valve port 18. The components of the disc
and balancing subassembly 54 are configured so that the force
applied by the balancing diaphragm 144 is approximately opposite
and equal to the force of the upstream pressure on the valve disc
22 to eliminate any influence of the upstream pressure on the
diaphragm subassembly 52 and thereby allowing for more accurate
control of the downstream pressure by the fluid regulating device
10.
[0031] Referring to FIGS. 3A and 3B, the valve disc 22 may include
the groove 32 formed in the intermediate surface 30, and the groove
32 may extend along the groove axis 34 extending along (or adjacent
to) the intermediate surface 30 normal to the longitudinal axis 24.
The groove axis 24 may be at least partially curved when viewed
along the longitudinal axis 24. For example, the groove axis 34 may
have a circular shape or a partially-circular shape when viewed
along the longitudinal axis 24, as illustrated in FIG. 3B. The
circular shape or a partially-circular shape may be concentric with
the longitudinal axis 24. The groove 32 may have any suitable
cross-sectional shape or combination of shapes when viewed along
the groove axis 34. For example, as illustrated in FIGS. 3A and 4,
the cross-sectional shape of the groove 32 may have a top wall 156
that is normal to the longitudinal axis when viewed along the
groove axis 34, the top wall being longitudinally offset from the
intermediate surface 130 towards the second end 154 of the valve
disc 22. The top wall 156 may be linear when viewed in
cross-section, or may be curved or partially curved when viewed in
cross-section. The top wall 156 may form a cross-sectional portion
of a planar surface 158 that extends along the groove axis 34 and
that may be normal or substantially normal to the longitudinal axis
24.
[0032] Referring again to FIGS. 3A and 4, the cross-sectional shape
of the groove 32 may have a first side wall 160a and a second side
wall 160b that each inwardly taper as each of the first and second
side walls 160a, 160b extends away from the intermediate surface
130 and towards the top wall 156. So configured, the groove 32 has
a trapezoidal cross-sectional shape when viewed normal to the
groove axis 34. The trapezoidal cross-sectional shape may be
symmetrically formed about an axis 162 normal to the groove axis
34. Instead of a trapezoid, the cross-sectional shape of the groove
32 may be rectangular or substantially rectangular, with the first
and second side walls 160a, 160b being parallel. Alternatively, the
groove 32 may have an at least partially curved cross-sectional
shape when viewed normal to the groove axis 34. That is, the groove
32 may have the cross-sectional shape of a portion of an oval
and/or of a portion of a circle. Further still, the groove 32 may
have the cross-sectional shape of a triangle or any other polygon.
When viewed in cross-section along the groove axis 34, the
intersection of the top wall 156 and first and second side walls
160a, 160b may be radiused, rounded, chamfered, etc. Alternatively,
the top wall 156 and first and second side walls 160a, 160b may
directly intersect to form an edge. The groove 32 may have a
constant cross-sectional shape along the entire length of the
groove 32 when viewed along the groove axis 34. Alternatively, the
cross-sectional shape of the groove may vary along the groove axis
34.
[0033] Alternative embodiments of a valve disc 22' are illustrated
in FIGS. 5A and 5B. These embodiments may be identical or
substantially identical to the embodiments of the valve disc 22
illustrated in FIGS. 1 to 4, with the exception being that the
intermediate surface 30' disposed radially inward of the sealing
surface 26 includes a protrusion 150 that extends along the
longitudinal axis 24 towards the valve port 18 (and towards the
second end 154 of the valve disc 22'). For example, a cross-section
of the intermediate surface 30' viewed normal to the longitudinal
axis 24 includes the first edge 164 and the second edge 166, and
the first edge 164 and the second edge 166 may converge as the
intermediate surface 30' extends towards the valve port 18.
[0034] The first edge 164 and the second edge 166 may be linear or
partially linear, or may be curved or partially curved.
Accordingly, the intermediate surface 30' may be at least partially
conical in shape. In the embodiment illustrated in FIG. 5A, the
intermediate surface 30' has the shape of a cone, and the tip of
the cone may be pointed or rounded. A base of the cone may have a
radial length that is between three times the longitudinal height
of the cone and equal to the longitudinal height of the cone.
Alternatively, the intermediate surface 30' may have a
cross-section shape of a parabola, as illustrated in FIG. 5B. A
radial width of the parabola may be between three times the
longitudinal height of the parabola and equal to the longitudinal
height of the parabola. The intermediate surface 30' may be
symmetrically formed about the longitudinal axis 24 or may be
asymmetrically formed.
[0035] As illustrated in FIG. 1, the fluid regulating device 10 may
optionally include a secondary device in the form of an
overpressure monitor 212 that operates to cut off the fluid flow
through the regulator valve 12 in an overpressure situation until
the downstream pressure is reduced after a failure of the actuator
20. The monitor 212 in the illustrated embodiment has a similar
configuration as the actuator 20, and the monitor 212 also operates
in a similar manner as the actuator 20. Because the monitor 212
only responds in the event that the downstream pressure exceeds a
cutoff pressure established by a diaphragm 248 and a control spring
252, a monitor diaphragm subassembly 242 and a disc and balancing
subassembly 244 are configured accordingly. A balancing spring 214
disposed between a spring seat 286 and a diaphragm retainer 292
biases a valve disc 222 to the normal open position. A coupler 272
and a control arm 276 are configured so that the coupler 272 only
drives the control arm 276 in the direction to move the valve disc
222 toward the closed position and into engagement with the
upstream side of the valve port 18 to cut off the fluid flow
through the regulator valve 12. A pin 272a of the coupler 272
engages the free end 276b of the control arm 276 to rotate the
control arm 276 when the diaphragm 248 and a piston 250 move upward
due to a downstream pressure exceeding the cutoff pressure.
Conversely, a top portion 272a of the coupler 272 is disposed
remotely from the control arm 276 so the downward movement of the
diaphragm 248 and piston 250 caused by decreases in the downstream
pressure do not cause movement of the control arm 276. Of course,
alternate configurations of overpressure monitors are known to
those skilled in the art, including monitors configured to close
when the downstream pressure drops below a low pressure cutoff, and
are contemplated by the inventors as having use in gas regulators
in accordance with the present disclosure.
[0036] When an operating demand is placed on the gas distribution
system, e.g., a user begins operating an appliance such as a
furnace, a stove, etc., the appliance draws gas from the outlet 16
and correspondingly the control cavity 44 of the actuator 20 and
the control cavity 232 of the monitor 212, thereby reducing the
pressure that is sensed by the diaphragms 58, 248. As the pressure
sensed by the diaphragm 58 decreases, a force imbalance occurs
between a control spring force and an outlet pressure force on the
diaphragm 58 such that the control spring 62 expands and displaces
the diaphragm 58 and piston 60 downward relative to the housing 42.
This causes the control arm 108 to pivot in the clockwise
direction, which in turn rotates the finger 113 relative to the
surface of the actuator stem 112. This allows the actuator stem 112
and the valve disc 22 to move away from the outlet 125 of the valve
port 18 due to the force of the balancing spring 148 to open the
regulator valve 12. At the same time, the pressure decrease may
also cause a force imbalance to occur between a control spring
force and an outlet pressure force on the diaphragm 248 such that
the control spring 252 expands and displaces the diaphragm 248 and
piston 250 downward relative to the housing 230. However, because
the upper portion of the coupler 272 is disposed remotely from the
control arm 276, the monitor 212 does not similarly respond to the
drop in pressure with movement of the valve disc 222.
[0037] When the demand is removed from the gas distribution system,
such as when the user shuts off the appliance, the regulator 10
initially responds by decreasing the fluid flow through the
regulator valve 12. As gas continues to flow through the valve port
18 and to the downstream portion of the system, the pressure
increases at the outlet 16 and, correspondingly, in the control
cavity 44 of the actuator 20 and the control cavity 232 of the
monitor 212. As the pressure sensed by the diaphragm 58 increases
and overcomes the control spring force, the diaphragm 58 and piston
60 are forced upward relative to the housing 42. The upward
movement causes the control arm 108 to pivot in the
counterclockwise direction, which in turn drives the actuator stem
112 and the valve disc 22 toward the valve port 18 to reduce the
fluid flow through the regulator valve 12. Under normal operating
conditions, the outlet pressure will drop to approximately the
actuator setpoint pressure and remain there until the downstream
demand changes in a manner that causes a response from by the
actuator 20.
[0038] The monitor cutoff pressure is greater than the actuator
setpoint pressure, and the monitor 212 does not typically respond
to pressure variations within the normal operating range of the
fluid regulating device 10. In the event of a failure of the
actuator 20 such as, for example, the rupturing of the diaphragm
58, the valve disc 22 may remain open despite increases in the
downstream pressure beyond the actuator setpoint pressure.
Eventually, the pressure at the sensing point of the Pitot tube 216
reaches the cutoff pressure of the monitor 212. The downstream
pressure communicated to the control cavity 232 by the monitor
branch 218 causes a force imbalance to occur between the control
spring force and the outlet pressure force on the diaphragm 248
such that the control spring 252 contracts and displaces the
diaphragm 248 and piston 250 upward relative to the housing 230.
When the piston 250 moves, the pin 272a of the coupler 272 rotates
the control arm 276 to drive the actuator 278 and move the valve
disc 222 into engagement with the valve port 18 to shut off the
fluid flow through the regulator valve 12. The monitor 212 will
continue to stop the fluid flow as long as the pressure at the
sensing point of the Pitot tube 216 remains above the monitor
cutoff pressure.
[0039] In operation, when the valve disc 22 is in the open position
(i.e., when the sealing surface 156 of the valve disc 22 does not
sealingly engage the valve port 18), fluid flows from the inlet 14
to the outlet 16 through the valve port 18. While in the open
position, a portion of the fluid flowing from the inlet 14 to the
outlet 16 passes through the one or more disc passages 155 and
enters the first cavity 156. The fluid within the first cavity 156
then comes into contact with the balancing diaphragm 144 such that
the surface of the balancing diaphragm 144 opposite the valve port
18 in fluid communication with the upstream pressure bearing on the
valve disc 22. In embodiments of the valve disc 22 that include the
groove 32 formed in the intermediate surface 30 (as illustrated in
FIGS. 3A and 3B), the groove profile improves "boost" at high inlet
pressures by distributing the inlet pressure as it acts on the
valve disc 22, thereby changing the balanced port inlet pressure
sense and, as a result, increasing capacity in the fluid regulating
device 10. In alternative embodiments of the valve disc 22'
illustrated in FIGS. 5A and 5B, the protrusion 150 acts to reduce
"boost" at low inlet pressures by redirecting flow as it acts on
the valve disc 22, thereby decreasing capacity in the fluid
regulating device 10. Also, by providing a plurality of balancing
springs 148 that each have a unique spring characteristics (e.g.,
spring force), a desired valve disc 22, 22' can be shipped with a
desired balancing springs 148 to provide a customizable set that
tunes the disc and balancing subassembly 54 to achieve desired flow
conditions.
[0040] While certain representative embodiments and details have
been shown for purposes of illustrating the invention, it will be
apparent to those skilled in the art that various changes in the
methods and apparatus disclosed herein may be made without
departing from the scope of the invention.
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